CPA CPA Operating Systems & Process Management

Question 1

What is the primary role of an operating system's process scheduler?

Accepted Answer

Manage CPU time allocation among processes

Answer

The process scheduler allocates CPU time among competing processes to maximize efficiency and responsiveness.

Question 2

Which scheduling algorithm gives the shortest average waiting time when all job lengths are known in advance?

Accepted Answer

Shortest Job First

Answer

Shortest Job First (SJF) minimizes average waiting time by always executing the process with the smallest CPU burst next.

Question 3

In operating systems, what is a 'race condition'?

Accepted Answer

A situation where output depends on unpredictable timing of concurrent operations

Answer

A race condition occurs when multiple threads access shared data concurrently and the result depends on the order of execution.

Question 4

What mechanism prevents two processes from simultaneously entering their critical sections?

Accepted Answer

Mutex lock

Answer

A mutex (mutual exclusion) lock ensures that only one process can enter a critical section at a time.

Question 5

Which state transition occurs when a process's time slice expires in a preemptive scheduler?

Accepted Answer

Running → Ready

Answer

When a time slice expires the scheduler preempts the process and moves it from Running back to Ready, so another process can run.

(CPA) Certified Associate Programmer Practice Test